CN105098142A

CN105098142A - Coating method for lithium-ion battery pole piece

Info

Publication number: CN105098142A
Application number: CN201410202747.5A
Authority: CN
Inventors: 耿丹
Original assignee: Shenzhen OptimumNano Energy Co Ltd
Current assignee: Shenzhen Anding New Energy Technology Development Co., Ltd.
Priority date: 2014-05-06
Filing date: 2014-05-06
Publication date: 2015-11-25
Anticipated expiration: 2034-05-06
Also published as: CN105098142B

Abstract

The invention discloses a coating method for a lithium-ion battery pole piece. The coating method comprises the following four steps: (1) fully stirring and dispersing conductive agent powder, binder powder and a solvent to prepare a conductive agent solution of a negative copper foil; (2) fully stirring and dispersing small-particle active substance powder, the binder powder and the solvent to prepare an active substance solution of a positive copper foil; (3) respectively coating reticular foils for a negative electrode and a positive electrode with the conductive agent and the active substance solution and rapidly drying the reticular foils; and (4) entering a coating process. Compared with the prior art, according to the coating method for the lithium-ion battery pole piece, the surfaces of the positive and negative foils are respectively coated with the conductive agent solution and the active substance solution in advance; and meshes on the foils are filled and leveled up; because the solution has viscidity, no material leakage during coating can be ensured; and meanwhile, the surface of each foil is coated with a solution layer, so that the strength is increased, and the problems that the foils are easy to crack and easy to break are effectively solved.

Description

A kind of coating process of electrodes of lithium-ion batteries

[technical field]

The present invention relates to field of lithium, particularly relate to a kind of coating process of electrodes of lithium-ion batteries.

[background technology]

In the performance requirement of lithium ion battery, high-energy-density and large multiplying power discharging the most important, especially in electric vehicle application, capacity in high-energy-density meaning same volume situation is higher, continuation of the journey energy is stronger, large multiplying power discharging means that the discharging current of battery is larger, can provide stronger power for the vehicles; The lifting of energy density can promote gram volume by material improvement, also can be promoted the internal volume utilance of single battery core by design.Pole piece foil thickness reduces or uses the foil having aperture, it is a kind of method being promoted energy density by design, foil thickness reduces to cause intensity to reduce, also can increase battery core internal resistance, and use the netted foil with aperture, fill active material at mesh place, effectively can promote energy density, and the active material of filling in mesh can obviously promote ionic conduction and transfer ability, and then promote high rate performance, therefore netted foil technique is favored by numerous battery production enterprise.

Traditional netted foil is when being coated with, an insoluble problem leaks material exactly, the wet slurry be coated on foil can stick on running roller before also not entering oven drying, follow-up coating cannot be carried out, even if state-of-the-art highly viscous slurry extrusion coated technology, can temporarily avoid Lou expecting, but pit and pit can be there is in mesh position in dry run, extreme influence is had to the follow-up performance of battery core, and netted foil reduces due to intensity, the problem such as cause easily occurring in battery core production process that pole piece fracture, winding fracture and foil are broken.

In view of above drawback, be necessary to provide a kind of coating process of electrodes of lithium-ion batteries to overcome above-mentioned defect in fact.

[summary of the invention]

The object of this invention is to provide a kind of coating process of electrodes of lithium-ion batteries, it not only puies forward the leakage material problem solving netted foil, also improves foil intensity simultaneously.

To achieve these goals, the present invention adopts following technical scheme: a kind of coating process of electrodes of lithium-ion batteries, the method comprises four steps, the first step, conductive agent powder, binding agent powder, solvent is fully stirred, disperses to prepare the conductive agent solution of negative copper foil; Second step, fully stirs granule active material powder, binding agent powder, solvent, disperses to prepare the active substance solution of positive pole aluminium foil; 3rd step, to be coated in conductive agent and active substance solution on negative pole and positive pole netted foil used and rapid draing respectively; 4th step, enters coating process.

One as the coating process of a kind of electrodes of lithium-ion batteries of the present invention is improved, and the conductive agent solution of described negative copper foil comprises: the conductive agent powder of 0.5%-3%, the binding agent powder of 0.5%-2.5%, the solvent of 94.5%-99%;

One as the coating process of a kind of electrodes of lithium-ion batteries of the present invention is improved; the active substance solution of described positive pole aluminium foil comprises: the granule active material powder that ratio is 0.5%-3%, particle diameter is 0.2-1.5um; the binding agent powder of 0.5%-2.5%, the solvent of 94.5%-99%.

When being coated with; owing to being coated with conductive agent solution and granule active substance solution respectively at negative copper foil and positive pole aluminium foil surface in advance; and carry out rapid draing; the mesh position of foil is filled and led up, and furthermore solution has certain viscosity, can not leak material when can guarantee coating like this; simultaneously; because foil surface has been coated with viscosity solution, add the intensity of foil, efficiently solve foil and easily split easily broken problem.

[accompanying drawing explanation]

Fig. 1 is the netted Copper Foil schematic diagram of negative pole of the coating process of a kind of electrodes of lithium-ion batteries of the present invention;

Fig. 2 is the negative pole netted Copper Foil electricity agent solution layer schematic diagram of the coating process of a kind of electrodes of lithium-ion batteries of the present invention;

Fig. 3 is the negative pole netted Copper Foil coating layer diagram of the coating process of a kind of electrodes of lithium-ion batteries of the present invention;

Fig. 4 is the netted aluminium foil schematic diagram of positive pole of the coating process of a kind of electrodes of lithium-ion batteries of the present invention;

Fig. 5 is the positive pole netted aluminium foil active substance solution layer schematic diagram of the coating process of a kind of electrodes of lithium-ion batteries of the present invention;

Fig. 6 is the positive pole netted aluminium foil coating layer diagram of the coating process of a kind of electrodes of lithium-ion batteries of the present invention.

[embodiment]

Please refer to shown in Fig. 1 to Fig. 6, below in conjunction with case study on implementation, the invention will be further described.

Execution mode is such:

Cathode pole piece coating process: by the conductive agent powder 13 of 0.5%-3%, the binding agent powder of 0.5%-2.5%, the solvent of 94.5%-99% fully stirs, disperses, reach solution without layering, soilless sticking, namely preparation becomes the conductive agent solution 14 of negative copper foil, then to be evenly coated in by conducting solution 14 on the Copper Foil 10 with mesh 12 and to carry out rapid draing, finally, the slurry 15 that will be coated with is coated in conducting solution 14 surface, then operation completes.

Anode pole piece coating process: the granule active material powder 23 that ratio is 0.5%-3%, particle diameter is 0.2-1.5um; the binding agent powder of 0.5%-2.5%; the solvent of 94.5%-99% fully stirs, disperses; reach solution without layering, soilless sticking; namely preparation becomes the active substance solution 24 of positive pole aluminium foil; again active substance solution 24 to be evenly coated on the aluminium foil 20 with mesh 22 and to carry out rapid draing; finally; the slurry 25 that will be coated with is coated in active substance solution 24 surface, then operation completes.

When being coated with, owing to being coated with conductive agent solution and active substance solution respectively at negative copper foil and positive pole aluminium foil surface in advance, and carry out rapid draing, the mesh position of foil is filled and led up, and furthermore solution has certain viscosity, can not leak material when can guarantee coating like this, simultaneously, because foil surface has been coated with viscosity solution, add the intensity of foil, efficiently solve foil and easily split easily broken problem.

The coating process of a kind of electrodes of lithium-ion batteries of the present invention, be not restricted to described in specification and execution mode, therefore additional advantage and amendment can easily be realized for the personnel of familiar field, therefore when not deviating from the spirit and scope of the universal that claim and equivalency range limit, the present invention is not limited to specific details, representational equipment and illustrates here and the examples shown described.

Claims

1. a coating process for electrodes of lithium-ion batteries, is characterized in that: the method comprises four steps, the first step, conductive agent powder, binding agent powder, solvent is fully stirred, disperses to prepare the conductive agent solution of negative copper foil; Second step, fully stirs granule active material powder, binding agent powder, solvent, disperses to prepare the active substance solution of positive pole aluminium foil; 3rd step, to be coated in conductive agent and active substance solution on negative pole and positive pole netted foil used and rapid draing respectively; 4th step, enters coating process.

2. the coating process of a kind of electrodes of lithium-ion batteries according to claim 1, is characterized in that: the conductive agent solution of described negative copper foil comprises: the conductive agent powder of 0.5%-3%, the binding agent powder of 0.5%-2.5%, the solvent of 94.5%-99%.

3. the coating process of a kind of electrodes of lithium-ion batteries according to claim 1; it is characterized in that: the active substance solution of described positive pole aluminium foil comprises: the granule active material powder that ratio is 0.5%-3%, particle diameter is 0.2-1.5um; the binding agent powder of 0.5%-2.5%, the solvent of 94.5%-99%.